Cutting is an increasingly popular behavior among teens—and it doesn't mean skipping classes, anymore. Cutting, with a paper clip, scissors, pen or other sharp object on the skin, is just one of a number of self-injurious behaviors that kids use to hurt themselves.

Wendy Lader, PhD, clinical director of S.A.F.E Alternatives and co-author of Bodily Harm, says self-harm is more prevalent than most people think. “Studies on adolescents in community samples report a lifetime prevalence between 15 and 20 percent,” she says.

So, why would kids purposefully cut themselves? The most common reason is control of emotions, according to Lader. “For kids experiencing intense emotions, it can be used to deaden the intensity. For those feeling a sense of numbness, it serves the opposite effect, helping them feel something,” Lader says.

Experts say for some adolescents, self-injury indicates other mental health concerns, such as depression. Others use is as a way to fit in with peers.

And this behavior can become addictive, according to Susan Bowman, licensed counselor and author of See My Pain: Creative Strategies and Activities for Helping Young People Who Self-Injure. “When kids cut themselves, it releases endorphins and they get a high from it,” she says. “It becomes a control issue: This is the way I release the pressure.”

There are clues that parents can watch for when it comes to self-injury. In addition to unexplained cuts and bruises, a change in communication, eating or sleeping patterns can be red flags. Though parents are understandably appalled at the thought of their child self-injuring, Bowman says this is exactly the reaction to avoid. “If you are shocked by a cut on their wrist, they may not trust you to accept and deal with what’s really bothering them,” she says. “They need caring and nurturing.”

So, how should you react? Here's some advice from the experts:

Communication is key. “Listen. Speak calmly, without judging, while expressing your love and concern,” Lader says. “Don’t try to offer your opinion or fix the problem. The goal is to foster open communication,”

Ask the right questions. Bowman says parents should use “what” and “how” questions, like “What makes you want to hurt yourself?”

Positive attention is a valuable part of the healing process. “Kids need attention when they are using positive coping skills and talking about their problems,” Bowman says.

Consider therapy. “A therapist can help determine if the child is experiencing some underlying issue that they don’t know how to identify or talk about,” says Lader. If you aren't sure how to choose a therapist, the school counselor might be a good place to start. Bowman also advises looking for someone experienced in adolescent issues, and specifically self-injury. “A combination of therapy techniques, such as cognitive, behavioral and creative arts therapy usually works best,” Bowman says.

Self-injury is a cry for help. Kids engaging in these behaviors desperately need parents to provide understanding and a willingness to listen.